We have made a cDNA library from the electric organ of Torpedo californica. An ll nucleotide primer which is complementary to a sequence about 150 nucleotides downstream from the encoded N-terminal amino acid was used to prime cDNA and electrophoresis of the product was performed on polyacrylamide gels. Individual cDNA bands were blotted on nitrocellulose filters and hybridized to a labeled probe of 14 nucleotides, representing the complementary strand. Three cDNA bands were positive and are presently under investigation.